REPRODUCTIVE ORGANS IN THE PRIMULACEA. 97 
reflect on the results, I think we are all but forced to conclude 
that the parallelism noticed above is accidental*, and that, even 
as the greatest capricity and uncertainty is manifested in the 
sexual conjunctions of the respective forms, so is there a like 
capricity and uncertainty in the degree of fertility thereby in- 
duced. In fine, as there is a general indefiniteness in the results 
of the reciprocal unions of normal hermaphrodite species, so I be- 
lieve (as above indicated) we shall find similar irregularities in 
the results of the reciprocal unions of the two forms of dimorphic 
species. 
Primula vulgaris and the var. alba present both forms; of the 
P. vulgaris, var. rubra, I have seen the long-styled form alone. I 
instituted a series of experiments on these forms, with the view 
of determining the results of their reciprocal unions. Certain of 
these are so remarkable, that I hesitate not a little in bringing 
them forward until I have had again an opportunity of repeating 
my experiments. From their bearings, however, on certain highly 
important points in theoretical natural science, I will (subject 
to the above reservation) venture to lay the results before the 
Society, and thus directing the attention of those interested in 
such phenomena to subjects well worthy a careful experimental 
examination, show also that my results, remarkable though they 
undoubtedly are, have a basis sufficiently extensive to justify me 
in regarding them as at least an approximation to the true func- 
tional relations of these plants. 
In the following Table I have given the results of my experi- 
ments on several plants of the above varieties, growing in pots 
and subjected to exactly similar treatment :— 
* The necessity for further experimentation on this point, however, is shown 
by the following cases mentioned by Mr. Darwin, ‘ Origin of Species,’ 3rd edit. 
p. 293, on the authority of Gartner: “namely, that yellow and white varieties 
of the same species of Verbascum when intercrossed produce less seed than do, 
either coloured varieties when fertilized with pollen from their own coloured 
flowers.” Again, “ that when yellow and white varieties of one species are 
crossed with yellow and white varieties of a DISTINCT species, more seed is prò- 
. duced by the crosses between the similarly coloured flowers than between those 
which are differently coloured.” We thus see that the functional relations of 
varieties of a species MAY extend to, and similarly correlate the varieties of DISTINCT 
species! 
